Moisture control device for rotary duplicating machines



y 1956 w. RITZERFELD ETAL 2,745,340

MOISTURE CONTROL DEVICE FOR ROTARY DUPLICATING MACHINES 4 Sheets-Sheet 1Filed Jan. 16, 1952 Fig. 4 17 HYVEHTGRS: WILH ELM R ITZERFELD Am)GERHARD RITZERFELD May 15, 1956 w. RITZERFELD EI'AL 2,745,340

MOISTURE CONTROL DEVICE FOR ROTARY DUPLICATING MACHINES Filed Jan. 16,1952 4 Sheets-Sheet 2 Fig. 2 o o INVENTORSI WILHELM RITZERFELD ANDGERHARD fin'zERFELD May 15, 1956 w. RITZERFELD EI'AL 2,745,340

MOISTURE CONTROL DEVICE FOR ROTARY DUPLICATING MACHINES Filed Jan. 16,1952 4 Sheets-Sheet 5 INVEHTORS.

\JILHELM RITZERFELD MD GERHARD RITZERFE'LD May 15, 1956 w. RITZERFELDEI'AL 2,745,340

MOISTURE CONTROL DEVICE FOR ROTARY DUPLICATING MACHINES 4 Sheets-Shem 4Filed Jan. 16, 1952 Fig. 4

INVEHTORSI ML E m RJTZE R FE'LDAnp GERHARD RITZERFELD United StatesPatent i MOISTURE CONTROL DEVICE FDR ROTARY DUPLICATING MACHINES WilhelmRitzer'feld and Gerhard Ritzerfeid,

' Berlin-Dahlem, Germany Application January 16, 1952, Serial No.266,692 Claims priority, application Germany January 22, 1951 12 Claims.(Cl. 101132.5)

The invention relates to rotary duplicating machines for printing frommirror-script originals capable of being reproduced on sheets(hereinafter called copy sheets) which have to be moistened by amoistening device, and more especially to such rotary duplicatingmachines which aiford an adjustable printing pressure for the printingelements and comprise a device for feeding a liquid to the moisteningdevice from a storage container or the like. Known rotary duplicatingmachines of this kind require, with an increasing number of copies made,an increase of the printing pressure and an increase of the amount ofliquid in order to enable obtaining a greater number of prints from thehectographic mirror-print original. With known machines of this kind,the control of the printing pressure was independent of the control ofthe feed of liquid to the moistening device. Both parts of the machinehad separately to be adjusted at short intervals during the operation,whereby mistakes in the operation were caused, and bad or imperfectcopies, or even considerable spoiling of the original, resulted. Sincethe operating conditions of the machines often change, this was adisadvantage in connection with duplicating machines-employing amoistening liquid.

With a view to avoiding or at least mitigating these disadvantages, theinvention consists in a rotary duplicating machine for printing frommirror-script originals capable of being reproduced on sheets which haveto be moistened by a mois'tening device, characterized by an operativeconnection between a mechanism for adjusting the printing pressure and amechanism for adjusting the feed of liquid to the moistening device.There may be provided an eccentric device for increasing the pressureexerted by a counter roller against the printing drum, an adjustingdevice for determining the stroke of the piston of a pump for theliquid, and a lever arrangement for jointly adjusting the efficiency ofthe counter roller and of the pump for the liquid. Alternatively, theremay be provided an eccentric device for increasing the pressure exertedby a counter roller against the printing drum, an adjusting device fordetermining the opening of a valve or valves for the feed of the liquid,and a lever arrangementfor jointly adjusting the efliciency of thecounter roller and the valve or valves. Owing to the operativeconnection, it is possible, in a single operation, to increase theprinting pressure as well as the amount of liquid by predeterminedamounts after predetermined numbers of copies have been made. Thereby,the danger of damaging or spoiling of the mirror-script originals bymoistening in excess due to errors is excluded or, at least, reduced.

According to a further refinement of the invention, a counting deviceactuat'able by the printing drum of the machine, for example over a wormand worm wheel, is provided, the counting device being arranged forautomatically elfecting the adjustment of the printing pressure and ofthe feed of the liquid, for example by means of a further worm and wormwheel, in dependence on the number of rotations performed by theprinting drum. The-counting device may be a predetermined counter2,745,340 Patented May 15,1956

2 operatively connected to a blocking pawl of a singlestroke coupling,the arrangement being such that the counting device, after reaching apredetermined count arrests the-printing drum by releasing the blockingvpawl of the single-stroke coupling.

A further improvement of the rotary duplicating machine consists in theprovision of a device, for example an electronic control device or adevice comprisinga control resistor, for controlling the speed ofprinting. Especially the provision of an electronic control device hasthe advantage that a control efiect may be obtained within a wide rangeof control without any substantial loss of power of the motor. To thisend, the control device'rnay comprise a thyrat'ron valve, a seleniumrectifier, a transformer, and one or more variable resistors forcontrolling the armature current of a direct current motor for drivingthe printing drum. A lever connection rnaybe provided between anadjusting mechanism for the printing pressure and the device forcontrolling the speed. A control of the number of rotations of thedirect current motor is elrected on converting an alternating current ofa main supply into a direct current While differentially clipping thepeaks of the alternating current. For performing the control, thearmature current of the direct current motor is controlled. Theelectronic control in connection with a duplicating machine using amoistening liquid has many advantages over hitherto known mechanicalcontrol devices and control devices comprising re sistors. Theelectronic control device may operate without noise, Without substantialloss of power, and is highly effective; moreover, by the possibility ofcontrolling the speed with increasing number of copies obtained from theoriginal, the possibility of utiliZing the original is essentiallyincreased since the printing speed is reduced by the alternation of thenumber of revolutions per unit of time and the moistened areas of thecopy sheets to be printed remain in contact with the original for alonger time and thereby exhaust the original to a greater extent evenafter it has already extensively been used.

Preferably, the electronic control device, if provided, is also coupledwith the printing mechanism or with the counting mechanism respectively.The-rotary duplicating machine in its preferred construction may operatecompletely automatically it being only necessary to set the machine tothe number of copies required after which the machine is started. Theentire subsequent operation is taken over by the mechanism of themachine,- if the machine is provided with means for automaticallyfeeding the copy sheets to the machine;

The invention also consists in a rotary duplicating'machine using aliquid'for moistenlng copy sheets, comprisin'gan el'eetroniccontroldevice.

To make the invention clearly understood reference will now be made tothe accompanying drawings, which are-given by way of example and inwhich:

Fig; l is a side view of a rotary duplicating machine comprising a pumpfor the 'control of the feed of the liquid, and means for controllingthe printing speed;

Fig. 2 is a circuit diagram of an arrangement for controlling the numberof revolutions per unit of time of a motor for 'driv'ingthe printingdrum;

Fig. 3 is a side view of a rotary duplicating machine comprisin a valvefor controlling the feed of the liquid; and

Fig. 4 is a side view of a device for automatically eontrelling theprintin process, and of a switching=off device for arresting theprinting drum.

In Figs 1, a printing drum 1 is rigidly connected to cam 2 for operatinga moistening device and rotated, in operation, the direction of thearrow A. A forked lever 4 tiltable aro nd a shaft 3 is rotated 'by thecm '2 in the direction of the arrow B, and presses, by means of api'ntion.

5, a piston 6 of a pump into a cylinder 7, whereby a moistening liquidcontained therein flows through a feed pipe 8 onto a moistening felt 9of a moistening device. A spring 10 returns the forked lever 4 after ithas left the region of greatest radius of the cam 2 into its initialposi- Thereby, the piston 6 of the pump is brought by a spring 11 intoabutment against an adjusting tube 13 displaceable in a sleeve 12 fixedrelatively to the frame of the machine. By means of a pin 14, theadjusting tube 13 is retained by a lever 15 in a position set for eachcase.

Thereby, the stroke of the piston 6 and the amount of the liquid fed isset. The adjustment of the lever 15 may be eifected manually as well assimultaneously with the adjustment of the printing pressure. On manualadjustment, at slidable member 18 is displaced in a slot 19 of the lever15 by means of a chain 17 guided in a fixed groove 16. The groove 16 isinclined relative to the slot 19 and thereby causes the lever 15, whichis pulled by a spring 20 against an abutment stud 21, to rotate aroundthe latter in the direction of the arrow D when the slideable member 18is displaced in the direction of the arrow C. The adjusting tube 13 isforced to participate in such rotation and presses the piston 6 of thepump more deeply into the cylinder 7 of the pump whereby the distancebetween the pin 5 and the forked lever 4 is increased. The

forked lever 4 is tilted through a total tilting angle that remainsconstant, but engages pin 5 only during movement through a smaller partof said angle. Correspondingly, the fed amount of liquid is smaller. Ona hand wheel 22, on which the chain 17 is Wound, a scale 23 is providedwhich, in conjunction with a fixed index mark 24, enables the amount ofthe liquid which is fed to be 'read off. The increase of the printingpressure by means of a counter roller 25 is eifected over a manuallyoperable lever 26 and requires an increased feed of the liquid. Themanually operable lever 26 is tiltable in the direction of the arrow Eand is fixed in a selected position by a notched segment 27 fixed inposition. With the displacement of the lever 26, a lug 28 is displacedin the direction of the arrow F and now replaces the abutment 21. Thedisplacement of the lug 28 in the direction of the arrow F, however,enables the lever 15 to tilt against the direction of the arrow D aroundits slideable member 18. I

Thereby the adjusting tube 13 is displaced against the direction of thearrow D. The spring 11 pulls the piston 6 of the pump, whereby thedistance between the pin 5 and the forked lever 4 is also decreased in astep-by-step manner according to the adjusted printing pressure. Thepiston 6 of the pump, thus, is in the maximal extreme case displacedduring the entire tilting movement of the forked lever 4 andcorrespondingly the amount of the liquid fed has also a maximal value.

Furthermore, an increase of the printing pressure requires a reductionof the number of rotations per unit of time of the printing drum 1. Thisis achieved by the varying of the number of rotations per unit of timeof a motor 29 driving the printing drum 1. The number of rotations perunit of time of the motor 29 is dependent on its armature current andfield current, which currents are controlled by an arrangement, the mainelements of which are a transformer 30 (see also Fig. 2), a rectifier31, and a thyratron valve 32. A variable resistor 33, whose tapping arm34 is coupled to toothed wheels 35, 36 and over a lug 37 to the lever 26determines the current flowing through the arrangement, the circuitdiagram of which is shown in Fig. 2.

An eccentric 39 rotatable around a shaft 38 can, in connection with theprinting drum 1, automatically tilt the lever 26 in the direction of thearrow E and thereby .tion of the arrow M, whereby the cam 81 rotates aroller 82 of an angular lever 84 tiltable around a shaft 83 in thedirection of the arrow N. With a pin 85,,a valve lifter 87 mounted on ashaft 86 is also tilted in the direction of the arrow N and, by means ofa nut 88, a valve rod 89 is lifted. Thereby, the outlet orifice in avalve chamber 90 is opened, and the liquid flows through a feed pipe 91onto a moistening felt 92 of the moistening device. When the roller 82has left the cam 81, a tension spring 93 returns the elements into theirinitial position.

In order to alter the flow times, and thereby to feed differently greatamounts of liquid to the felt 92, the path of the roller 82 on the cam81 is increased or shortened. To this end, the shaft 83 is displaced insuch a manner that the pin 85 becomes the centre of rotation of theangular lever 84, whereby the roller 82 is tilted in the direction ofthe arrow N away from the cam 82 or against the direction of the arrow Ntowards the cam 82. The first movement is used for reducing the amountof liquid fed, the latter for increasing it. The position of the shaft83 is determined by the lever 97 over a lug 96 rectilinearly guided byupstanding studs 94 and 95. The adjustment of the lever 97 can beeffected manually as well as simultaneously with the adjustment of theprinting pressure. On manual adjustment, a slidable member 100 isdisplaced in a slot 191 of the lever 97 by means of a chain 99 guided ina groove 98 fixed in position. The inclined position of the groove 98relative to the slot 101 causes the lever 97, which is drawn by a spring102 against an abutment stud 103 to tilt around the latter in thedirection of the arrow P on displacement of the slidable member 189 inthe direction of the arrow 0, while the displacement referred to aboveof the lug 96 takes place. On a hand wheel 104, on which the chain 99 iswound, a scale 105 is fixed which, in conjunction with a fixed indexmark 106 affords a possibility of reading off the fed amount of liquid.The increase of the printing pressure of a counter roller 107 iseifected over a manually operable lever 168 and requires the feed of agreater amount of liquid. The lever 198 is tilted in a direction of thearrow Q and is kept in a set position by a notched segment 189 fixed inposition. With this displacement, a lug 110 is displaced in thedirection of the arrow R and replaces the abutment stud 103. However,the displacement of the lug 110 in the direction of the arrow R causesthe lever 97 to tilt against the direction of the arrow P around itsslidable member 100, whereby also the lug 96 is pulled against thedirection of the arrow P. Thereby, the angular lever 84 rotates aroundits pin 85 and penetrates more deeply into the curved path of the cam81, the roller 82 being lifted by the cam 81 during a greater distance,the flow time and therewith the amount of liquid flowing out of astorage container 111 becomes greater.

The reduction of the number of rotations per unit of time of theprinting drum 80 on increasing printing pressure of the counter roller107 is achieved over the lug 112 by displacing the lever 108 as hasalready been described with reference to Fig. l. r

' In Fig. 4, a printing drum 40 rotates in the direction of the arrow Gtogether with a worm 41 rigidly connected thereto, and thereby drives atoothed worm wheel 42 and a shaft 45 mounted in bearings 43 and 44.together with its conical wheel 46 and its worm 47. By means of aconical wheel 48, driven by the conical wheel 46, a.

pointer 49 is rotated in the direction of the arrow H, the pointerhaving been preset on a scale 50 to a desired number of copy sheets.Before reaching a zero position, a pin 51 of the pointer 49 engages anabutment 52 on a pawl 54 tiltable around a shaft 53 of the conical wheel48, the pawl being lifted out of recess 55 of a blocking disc 56 whenthe pointer 49 reaches its zero position. A release member 57 is pulleyby a spring 58 in the direction of the arrow I towards an abutment'59and abuts against the pin 60 of the blocking disc 56. Release member 57enters with its own abutment edge 61 intothe 'member 54 and rotates dueto spring 56'. to aposition in which pin so releases member 51.-when-games reaches the abutment edgefiLit is tilted around ashaft Duringthe rotation-ofthe'shaft 45, the worm'47 drives a toothed segment 66,which by means of its elongated hole 67 carries with it a pin 69 fixedon a-l'ever 68. The

lever 68 is fixed on a'rotatable shaft 70' to which also an eccentric71- is keyed which corresponds to member 39 in Fig. l. The eccentric 71serves for controlling the printing pressure of a counter roller, whichmay be a rubber roller, against the printing drum- 40'. An' elongatedhole 72 and the elongated hole 67' of'the'toothed segment 66 enable amanual displacement of the eccentric 71 by displacing a handle 73 in thedirection of the arrow' L, whereby the toothed'segment 66is disengaged.

What we claim'is:

1. Ina rotary duplicating machine, in combination; a rotary printing,drum member; apressure member for pressing sheets against said printingdrum member; adjusting means connected to one of said last mentionedmembers for adjusting the printingpressure; acounting device connectedto said printing drum member and counting turning movements of the samefor counting the number of sheets printed; and'm'otion transmittingmeans connecting said counting device with said adjusting means in suchmanner that the printing pressure is increased in accordance with thenumber of turning movements of said drum memberc'ounted by said countingdevice, and thereby in accordance withthe number of printed sheets. p

2. In a'r'otary duplicating machine, in combination, moistening meansfor moistening sheets to be printed;

supply means for supplying a liquid to said moistening means;controlmeans for controlling the amount of liquid supplied by saidsupply means to said moistening means; a rotary printing drum member; apressure memher for pressing sheets against said printing drum member;adjusting means connected to one of said lastmeutioned members .foradjusting the printing pressure; a

counting device connected to said printing drum member and countingturning movements of the same for counting the number of sheets printed;first motion transmitting means connecting said counting device withsaid adjusting means in such manner that the printing pressure isincreased in accordance with the number of turning movements of saiddrum member counted by said counting device; and second motiontransmitting means connecting said adjusting means with said controlmeans in such manner that the amount of liquid supplied to saidmoistening means is increased in accordance with an increase of theprinting pressure, and thereby in accordance with the number of printedsheets.

3. In a rotary duplicating machine, in combination, a rotary printingdrum member; a pressure member for pressing sheets against said printingdrum member; adjusting means connected to one of said last mentionedmembers for adjusting the printing pressure; drive means for rotatingsaid printing drum member; regulating means for regulating the rotaryspeed of said drive means and thereby the rotary speed of said drummember; motion transmitting means connecting said adjusting means withsaid regulating means in such manner that the rotary speeds of saiddrive means and of said drum member are decreased in accordance with anincrease of the printing pressure; and operating means for operation ofsaid motion transmitting means for simultaneous regulation of the rotaryspeed of said drum member and of the printing pressure.

4. In a rotary duplicating machine, in combination, moistening means formoistening sheets to be printed; supply means for supplying a liquid tosaid moistening means; control means for controlling the amount ofliquid supplied by said supply means, to said moistening means;arotaryprinting drum-member; a pressure-member' forpressing sheets againstsaidprinting drum member; adjusting means connected to one of said lastmentioned members for adjustingtheprinting pressure; drive means forrotatlng'said printing drum member; regulating means'for regulatingtherotary speed of said drive meansa'nd thereby the rotary speed of saiddrum member; first motion transmitting means connectingsaid ad justingmeans with said regulating means in such manner that the rotary speed ofsaid drum member is decreased in accordance with an increase of theprinting pressure; second motion transmitting means connecting saidadjusting means with said control means in such manner that the amountof liquidsu plied to said moistening means'is increased in accordancewith an increase of the printing pressure; and operating meansconnectedto'said first and second motion transmitting means to acmate the samefor simultaneous regulation of the rotary speed of said drum member, ofthe printing pressure; and of the amount of liquid supplied'to themoistening means.

5. In a rotary duplication machine, in combination, moistening means formoistening sheets to be printed; pump means including cylinder means andpiston means for supplying a liquid to said moistening means; controlmeans for adjusting the stroke of said piston means 'for varying betweendifferent amounts the amount of liquid supplied by said pump means tosaid moistening means for sprinting o eration; a rotary printing drummember;

ner that the amount of su plied liquid is increased to correspond toincreased printing pressure.

'6. An arrangement as claimed in claim 5 including a a cam rotating withsaid drum member; a ivoted actuating member actuated by said cam toperform a rocking movement; a pin secured to said piston meansandlocated in the path of said rocking member so that said piston'mea'ns'is moved when said rocking member engages said pin; and whereinsaid control means include means for adjusting the position of saidpiston means and of said pin with respect to said actuating member sothat said pin may be engaged by said actuating member only during partof the rocking movement of the same for reducing the stroke of saidpiston means.

7. In a rotary duplicating machine, in combination, moistening means formoistening sheets to be printed; pump means including a cylinder meansand piston means for supplying a liquid to said moistening means; apiston rod fixed to said piston means; a stop fixed on said piston rod;an adjustable stop means cooperating with said abutment; a lever meanspivotally connected to said abutment means for adjusting the position ofthe same; an operating lever; a link means connecting said operatinglever with said lever means so that the position of said abutment meansis adjusted when said operating lever is operated; a

rotary printing drum member; a pressure member for means so that saidpin is engaged by said rocking actuat-' ing member only during part ofsaid rocking movement of the same, whereby the piston stroke isadjusted.

8. In a rotary duplicating machine, in combination, a rotary printingdrum member; a pressure member for pressing sheets against said printingdrum member; an operating lever; link means connecting said operatinglever with said pressure member; a rotary cam means engaging .saidoperating lever for actuating'the same; a reducing transmiss onconnecting said rotary drum'member with eration of said operating leverby said cam means in accordance with the number of sheets printed bysaid drum member.

9. In a rotary duplicating machine, in combinatioma rotary printing drummember; a pressure member for pressing sheets against said printing drummember; adjusting means connected to one of said last mentioned membersfor adjusting'the printing pressure; electric motor means for rotatingsaid printing drum member; regulating means for regulating the rotaryspeed of said electric motor means and thereby the rotary speed of saiddrum member, said regulating means including variable resistor meansassociated with said electric motor means; motion transmitting meansconnecting said adjusting means with said regulating means in suchmanner that the rotary speeds of said motor means and of said drummember are decreased in accordance with an increase of'the printingpressure; and operating means for operation of said motion transmittingmeans for-simultaneous regulation of the rotary speed of saiddrum memberand of the printing pressure.

10. An arrangement as claimed in claim 3 :wherein said drive means is adirect current motor means, and

moistening'means for moistening sheets to be printed;

variable feed pump means for supplying a liquid to said moisteningmeans, saidpump means including a movable :elem ent movable between aplurality of positions for varying the output of said pump means forvarying between difierent amounts the amount of liquid supplied by said.pump means to said moistening means for a printing operation; a rotaryprinting drum member; a pressure mem -ber for pressing sheets againstsaid printing drum mem- .moistening'means for moistening sheets to beprinted;

ber;.adjusting means connected, to one of said last-mentioned membersand beingmovable between a plurality of operativepositions for adjustingthe printing pressure for a printing operation; operating meansconnected to said .adjustingmeans and being movablebetween a pluralityof positions for moving said adjusting means. between said operativepositions of, thesame; and motion-transmitting means connecting saidoperating means with said movable element of said pump means for movingsaid element between said positionsof the same for simultaneousadjustment of the amount of liquid supplied to said moistening means andof, the printing pressure in such a manner .thatthe amountof suppliedliquid is increased to correspond to increased printing pressure.

. 12. In arotary duplicating machine, in combination,

supply means for supplying a liquid to said moistening means; valvemeans including a value opening member movable through a strokeincluding a plurality of positions of said valve opening-member forvarying between different amounts theamount of liquid supplied by saidsupply means to said moistening means for a printing operation; a rotaryprinting drum member; a pressure member for pressing sheets against-saidprinting drumi'member; an

operating member; a link connecting said operating member with saidpressure member; anda lever system connecting said operating member withsaid movable valve opening member for operating the same between saidpositions depending upon the printing pressure of said pressure memberin such amanner that the amount of suppli'ed'liquid is increased tocorrespond to increased printing pressure. I I I v References Cited inthe file of this'patent UNITED STATES PATENTS 1,183,529 Braseur 'May 16,1916 2,041,943 McCain 'et al.'- ..L May 26, 1936 2,221,634 Ford Nov. 12,1940 2,225,749 Marchev Dec. 24, 1940 2,231,639 Ritzerfeld Feb, 11, 19412,238,359 Copeland Apr. 15, 1941 Morrison Nov. 11, 1941

